Workpiece Processing Apparatus with Plasma and Thermal Processing Systems

ABSTRACT

A processing apparatus for processing a workpiece is presented. The processing apparatus includes a processing chamber, a plasma chamber separated from the processing chamber disposed on a first side of the processing chamber, and a plasma source configured to generate a plasma in the plasma chamber. One or more radiative heat sources configured to heat the workpiece disposed on a second and opposite side of the first side of the processing chamber. A dielectric window is disposed between the workpiece support and the one or more heat sources. The processing apparatus includes a rotation system configured to rotate the workpiece, the rotation system comprising a magnetic actuator.

FIELD

The present disclosure relates generally to semiconductor processingequipment, such as equipment operable to perform plasma processing andthermal processing of a workpiece.

BACKGROUND

Plasma processing is widely used in the semiconductor industry formaterials deposition, materials modification, materials removal, andrelated processing of semiconductor wafers and other substrates. Plasmasources (e.g., inductively-coupled plasma source, capacitively-coupledplasma source, microwave plasma source, electron cyclotron resonanceplasma source, etc.) are often used for plasma processing to producehigh density plasma and reactive species for processing substrates.Reactive species in plasma can include positively and negatively chargedions, negatively charged electrons, charge-neutral radicals and otherenergetic neutral particles. In order to avoid charge damage ofmaterials, charged species from a plasma generated in a remote plasmachamber can be filtered out while charge neutral radicals and otherenergetic neutral particles can pass through a separation grid into aprocessing chamber to treat a substrate, such as a semiconductor wafer.

Thermal processing is also used for processing workpieces. Generally, athermal processing chamber as used herein refers to a device that heatsworkpieces, such as semiconductor workpieces. Such devices can include asupport plate for supporting one or more workpieces and an energy sourcefor heating the workpieces, such as heating lamps, lasers, or other heatsources. During heat treatment, the workpiece(s) can be heated undercontrolled conditions according to a processing regime.

Many thermal treatment processes require a workpiece to be heated over arange of temperatures so that various chemical and physicaltransformations can take place as the workpiece is fabricated into adevice(s). During rapid thermal processing, for instance, workpieces canbe heated by an array of lamps through the support plate to temperaturesfrom about 300° C. to about 1,200° C. over time durations that aretypically less than a few minutes. During these processes, a primarygoal can be to reliably and accurately measure a temperature of theworkpiece.

Plasma processing and thermal treatments often require two separatedevices in order to effectively process workpieces, increasingmanufacturing costs and time. Accordingly, improved processingapparatuses capable of performing both plasma processing and thermaltreatments are desired.

SUMMARY

Aspects and advantages of embodiments of the present disclosure will beset forth in part in the following description, or may be learned fromthe description, or may be learned through practice of the embodiments.

Aspects of the present disclosure are directed to a processing apparatusfor processing a workpiece. The processing apparatus includes aprocessing chamber; a plasma chamber separated from the processingchamber, the plasma chamber disposed on a first side of the processingchamber; a gas supply system configured to deliver one or more processgases to the plasma chamber; a plasma source configured to generate aplasma from the one or more process gases in the plasma chamber; aworkpiece support disposed within the processing chamber, the workpiecesupport configured to support a workpiece, wherein a back side of theworkpiece faces the workpiece support; one or more radiative heatsources configured on a second and opposite side of the first side ofthe processing chamber, the radiative heating sources configured to heatthe workpiece from the back side of the workpiece; a dielectric windowdisposed between the workpiece support and the one or more radiativeheat sources; and a rotation system configured to rotate the workpiece,the rotation system comprising a magnetic actuator.

These and other features, aspects and advantages of various embodimentswill become better understood with reference to the followingdescription and appended claims. The accompanying drawings, which areincorporated in and constitute a part of this specification, illustrateembodiments of the present disclosure and, together with thedescription, serve to explain the related principles.

BRIEF DESCRIPTION OF THE DRAWINGS

Detailed discussion of embodiments directed to one of ordinary skill inthe art are set forth in the specification, which makes reference to theappended figures, in which:

FIG. 1 depicts an example processing system according to example aspectsof the present disclosure;

FIG. 2 depicts an example processing system according to example aspectsof the present disclosure;

FIG. 3 depicts an example processing system according to example aspectsof the present disclosure;

FIG. 4 depicts an example processing system according to example aspectsof the present disclosure;

FIG. 5 depicts an example processing system according to example aspectsof the present disclosure;

FIG. 6 depicts an example magnetic actuator according to example aspectsof the present disclosure;

FIG. 7 depicts an example magnetic actuator according to example aspectsof the present disclosure;

FIG. 8 depicts an example processing system according to example aspectsof the present disclosure;

FIG. 9 depicts an example processing system according to example aspectsof the present disclosure;

FIG. 10 depicts an example processing system according to exampleaspects of the present disclosure;

FIG. 11 depicts an example processing system according to exampleaspects of the present disclosure;

FIG. 12 depicts an example processing system according to exampleaspects of the present disclosure;

FIG. 13 depicts an example post plasma gas injection system according toexample embodiments of the present disclosure;

FIG. 14 depicts an example processing system according to exampleaspects of the present disclosure;

FIG. 15 depicts an example processing system according to exampleaspects of the present disclosure;

FIG. 16 depicts an example pumping plate according to example aspects ofthe present disclosure; and

FIG. 17 depicts an example flowchart of a method according to exampleaspects of the present disclosure.

DETAILED DESCRIPTION

Reference now will be made in detail to embodiments, one or moreexamples of which are illustrated in the drawings. Each example isprovided by way of explanation of the embodiments, not limitation of thepresent disclosure. In fact, it will be apparent to those skilled in theart that various modifications and variations can be made to theembodiments without departing from the scope or spirit of the presentdisclosure. For instance, features illustrated or described as part ofone embodiment can be used with another embodiment to yield a stillfurther embodiment. Thus, it is intended that aspects of the presentdisclosure cover such modifications and variations.

Various workpiece processing treatments can require plasma treatment,heat treatment, or both. Typically, plasma treatments and heattreatments, such as rapid thermal processing, must be performed indifferent devices or processing chambers in order to accurately controlprocess parameters. Furthermore, it has been difficult to obtainaccurate workpiece temperature measurements of workpieces during plasmaand thermal processing.

Accordingly, aspects of the present disclosure provide a number oftechnical effects and benefits. For instance, the plasma processingapparatus provided herein allows for the ability to conduct both plasmaand thermal treatments in the same processing chamber, thus savingfabrication time and money and can lead to reduce footprint insemiconductor processing facilities. Furthermore, the apparatus providedherein includes a rotation system including a magnetic actuator capableof efficiently rotating the workpiece during processing.

Variations and modifications can be made to these example embodiments ofthe present disclosure. As used in the specification, the singular forms“a,” “and,” and “the” include plural referents unless the contextclearly dictates otherwise. The use of “first,” “second,” “third,” etc.,are used as identifiers and are not necessarily indicative of anyordering, implied or otherwise. Example aspects may be discussed withreference to a “substrate,” “workpiece,” or “workpiece” for purposes ofillustration and discussion. Those of ordinary skill in the art, usingthe disclosures provided herein, will understand that example aspects ofthe present disclosure can be used with any suitable workpiece. The useof the term “about” in conjunction with a numerical value refers towithin 20% of the stated numerical value.

FIG. 1 depicts an example plasma processing apparatus 100 that can beused to perform processes according to example embodiments of thepresent disclosure. As illustrated, plasma processing apparatus 100includes a processing chamber 110 and a plasma chamber 120 that isseparated from the processing chamber 110. Processing chamber 110includes a workpiece support 112 or pedestal operable to hold aworkpiece 114 to be processed, such as a semiconductor wafer. In thisexample illustration, a plasma is generated in plasma chamber 120 (i.e.,plasma generation region) by an inductively coupled plasma source 135and desired species are channeled from the plasma chamber 120 to thesurface of workpiece 114 through a separation grid assembly 200.

Workpiece 114 can be or include any suitable workpiece, such as asemiconductor workpiece, such as a silicon wafer. In some embodiments,workpiece 114 can be or include a lightly doped silicon wafer. Forexample, a lightly doped silicon wafer can be doped such that aresistivity of the silicon wafer is greater than about 0.1 Ω·cm, such asgreater than about 1 Ω·cm.

Aspects of the present disclosure are discussed with reference to aninductively coupled plasma source for purposes of illustration anddiscussion. Those of ordinary skill in the art, using the disclosuresprovided herein, will understand that any plasma source (e.g.,inductively coupled plasma source, capacitively coupled plasma source,etc.) can be used without deviating from the scope of the presentdisclosure.

The plasma chamber 120 includes a dielectric side wall 122 and a ceiling124. The dielectric side wall 122, ceiling 124, and separation grid 200define a plasma chamber interior 125. Dielectric side wall 122 can beformed from a dielectric material, such as quartz and/or alumina.Dielectric side wall 122 can be formed from a ceramic material. Theinductively coupled plasma source 135 can include an induction coil 130disposed adjacent the dielectric side wall 122 about the plasma chamber120. The induction coil 130 is coupled to an RF power generator 134through a suitable matching network 132. The induction coil 130 can beformed of any suitable material, including conductive materials suitablefor inducing plasma within the plasma chamber 120. Process gases can beprovided to the chamber interior 125 from gas supply 155 and annular gasdistribution channel 151 or other suitable gas introduction mechanism(e.g. a showerhead). When the induction coil 130 is energized with RFpower from the RF power generator 134, a plasma can be generated in theplasma chamber 120. In a particular embodiment, the plasma processingapparatus 100 can include an optional grounded Faraday shield 128 toreduce capacitive coupling of the induction coil 130 to the plasma. Thegrounded Faraday shield 128 can be formed of any suitable material orconductor, including materials similar or substantially similar to theinduction coil 130.

As shown in FIG. 1, a separation grid 200 separates the plasma chamber120 from the processing chamber 110. The separation grid 200 can be usedto perform ion filtering from a mixture generated by plasma in theplasma chamber 120 to generate a filtered mixture. The filtered mixturecan be exposed to the workpiece 114 in the processing chamber 110.

In some embodiments, the separation grid 200 can be a multi-plateseparation grid. For instance, the separation grid 200 can include afirst grid plate 210 and a second grid plate 220 that are spaced apartin parallel relationship to one another. The first grid plate 210 andthe second grid plate 220 can be separated by a distance.

The first grid plate 210 can have a first grid pattern having aplurality of holes. The second grid plate 220 can have a second gridpattern having a plurality of holes. The first grid pattern can be thesame as or different from the second grid pattern. Charged particles canrecombine on the walls in their path through the holes of each gridplate 210, 220 in the separation grid. Neutral species (e.g., radicals)can flow relatively freely through the holes in the first grid plate 210and the second grid plate 220. The size of the holes and thickness ofeach grid plate 210 and 220 can affect transparency for both charged andneutral particles.

In some embodiments, the first grid plate 210 can be made of metal(e.g., aluminum) or other electrically conductive material and/or thesecond grid plate 220 can be made from either an electrically conductivematerial or dielectric material (e.g., quartz, ceramic, etc.). In someembodiments, the first grid plate 210 and/or the second grid plate 220can be made of other materials, such as silicon or silicon carbide. Inthe event a grid plate is made of metal or other electrically conductivematerial, the grid plate can be grounded. In some embodiments, the gridassembly can include a single grid with one grid plate.

In some embodiments, the grid plate can have one or more coolingmechanisms disposed therein for cooling the grid plate during operationof the processing apparatus. For example, one or more cooling channelscan be disposed in the grid plate. Air or fluid (e.g., water) can bepumped through the cooling channels to decrease the temperature of thegrid plate. Other known cooling chemicals can be pumped through thecooling channels for cooling the grid plate.

Example embodiments of a processing apparatus will now be discussed withreference to FIGS. 1-5 and 812. As shown in FIG. 1, according to exampleaspects of the present disclosure, the apparatus 100 can include a gasdelivery system 155 configured to deliver process gas to the plasmachamber 120, for instance, via gas distribution channel 151 or otherdistribution system (e.g., showerhead). The gas delivery system caninclude a plurality of feed gas lines 159. The feed gas lines 159 can becontrolled using valves 158 and/or gas flow controllers 185 to deliver adesired amount of gases into the plasma chamber as process gas. The gasdelivery system 155 can be used for the delivery of any suitable processgas. Example process gases include, oxygen-containing gases (e.g. O₂,O₃, N₂O), hydrogen-containing gases (e.g., H₂, D₂), nitrogen-containinggas (e.g. N₂, NH₃, N₂O), fluorine-containing gases (e.g. CF₄, C₂F₄,CHF₃, CH₂F₂, CH₃F, SF₆, NF₃), hydrocarbon-containing gases (e.g. CH₄),or combinations thereof. Other feed gas lines containing other gases canbe added as needed. In some embodiments, the process gas can be mixedwith an inert gas that can be called a “carrier” gas, such as He, Ar,Ne, Xe, or N₂. A control valve 158 can be used to control a flow rate ofeach feed gas line to flow a process gas into the plasma chamber 120. Inembodiments, the gas delivery system 155 can be controlled with a gasflow controller 185.

The workpiece 114 to be processed is supported in the processing chamber110 by the workpiece support 112. The workpiece support 112 can be aworkpiece support operable to support a workpiece 114 during thermalprocessing (e.g., a workpiece support plate). Workpiece support 112 canbe or include any suitable support structure configured to supportworkpiece 114, such as to support workpiece 114 in processing chamber110. In some embodiments, workpiece support 112 can be configured tosupport a plurality of workpieces 114 for simultaneous thermalprocessing by a thermal processing system. In some embodiments,workpiece support 112 can rotate workpiece 114 before, during, and/orafter thermal processing. In some embodiments, workpiece support 112 canbe transparent to and/or otherwise configured to allow at least someelectromagnetic radiation to at least partially pass through workpiecesupport 112. For instance, in some embodiments, a material of workpiecesupport 112 can be selected to allow desired electromagnetic radiationto pass through workpiece support 112, such as electromagnetic radiationthat is emitted by workpiece 114. In some embodiments, workpiece support112 can be or include a quartz material, such as a hydroxyl free quartzmaterial.

Workpiece support 112 can include one or more support pins 115, such asat least three support pins, extending from workpiece support 112. Insome embodiments, workpiece support 112 can be spaced from the top ofthe processing chamber 110, such as spaced from separation grid 220. Insome embodiments, the support pins 115 and/or the workpiece support 112can transmit heat from heat sources 140 and/or absorb heat fromworkpiece 114. In some embodiments, the support pins 115 can be made ofquartz.

Processing apparatus 100 can include one or more heat sources 140. Insome embodiments, heat sources 140 can include one or more heating lamps141. For example, heat sources 140 including one or more heating lampscan emit electromagnetic radiation to heat workpiece 114. In someembodiments, for example, heat sources 140 can be broadbandelectromagnetic radiation sources including arc lamps, tungsten-halogenlamps, any other suitable heating lamp, or combinations thereof. In someembodiments, heat sources 140 can be monochromatic electromagneticradiation sources including light-emitting diodes, laser diodes, anyother suitable heating lamps, or combinations thereof. The heat source140 can include an assembly of heating lamps 141, which are positioned,for instance, to heat different zones of the workpiece 114. The energysupplied to each heating zone can be controlled while the workpiece 114is heated. Further, the amount of radiation applied to various zones ofthe workpiece 114 can also be controlled in an open-loop fashion. Inthis configuration, the ratios between the various heating zones can bepre-determined after manual optimization. In other embodiments, theamount of radiation applied to various zones of the workpiece 114 can becontrolled in a closed-loop fashion.

In certain embodiments, directive elements, such as for example,reflectors 800 (e.g., mirrors) can be configured to directelectromagnetic radiation from one or more heating lamps 141 towards aworkpiece 114 and/or workpiece support 112. For example, one or morereflectors 800 can be disposed with respect to the heat sources 140 asshown in FIGS. 4-5 and 11-12. One or more cooling channels 802 can bedisposed between or within the reflectors 800. As shown by arrows 804 inFIGS. 5 and 12, ambient air can pass through the one or more coolingchannels 802 to cool the one or more heat sources 140, such as the heatlamps 141.

According to example aspects of the present disclosure, one or moredielectric windows 108 can be disposed between the heat source 140 andthe workpiece support 112. According to example aspects of the presentdisclosure, window 108 can be disposed between workpiece 114 and heatsources 140. Window 108 can be configured to selectively block at leasta portion of electromagnetic radiation (e.g., broadband radiation)emitted by heat sources 140 from entering a portion of the processingchamber 110. For example, window 108 can include opaque regions 160and/or transparent regions 161. As used herein, “opaque” means generallyhaving a transmittance of less than about 0.4 (40%) for a givenwavelength, and “transparent” means generally having a transmittance ofgreater than about 0.4 (40%) for a given wavelength.

Opaque regions 160 and/or transparent regions 161 can be positioned suchthat the opaque regions 160 block stray radiation at some wavelengthsfrom the heat sources 140, and the transparent regions 161 allow forother components of the apparatus 100 to freely interact with radiationin processing chamber 110 at the wavelengths blocked by opaque regions160. In this way, the window 108 can effectively shield the processingchamber 110 from contamination by heat sources 140 at given wavelengthswhile still allowing the heat sources 140 to heat workpiece 114. Opaqueregions 160 and transparent regions 161 can generally be defined asopaque and transparent, respectively, to a particular wavelength; thatis, for at least electromagnetic radiation at the particular wavelength,the opaque regions 160 are opaque and the transparent regions 161 aretransparent.

Window 108, including opaque regions 160 and/or transparent regions 161,can be formed of any suitable material and/or construction. In someembodiments, dielectric window 108 can be or include a quartz material.Furthermore, in some embodiments, opaque regions 160 can be or includehydroxyl (OH) containing quartz, such as hydroxyl doped quartz (e.g.,quartz that contains significant amounts of hydroxyl groups), and/ortransparent regions 161 can be or include hydroxyl free quartz (e.g.,quartz contains minimum amounts of hydroxyl groups). Advantages ofselecting hydroxyl doped quartz and hydroxyl free quartz materials caninclude ease of manufacturing. Additionally, hydroxyl doped quartz andhydroxyl free quartz can exhibit desirable wavelength blockingproperties in accordance with the present disclosure. For instance,hydroxyl doped quartz can block radiation having a wavelength of about2.7 micrometers, while hydroxyl free quartz can be transparent toradiation having a wavelength of about 2.7 micrometers.

One or more exhaust ports 921 can be disposed in the processing chamber110 that are configured to pump gas out of the processing chamber 110,such that a vacuum pressure can be maintained in the processing chamber110. For example, process gas can flow from the plasma chamber 120through the one or more separation grids 200 and enter the processingchamber 110 according to the arrows as depicted in FIGS. 5 and 12. Theprocess gas is exposed to the workpiece 114 and then flows around eitherside of the workpiece 114 and is evacuated from the processing chamber110 via one or more exhaust ports 921. The flow of the process gas isshown by arrows 806 in FIGS. 5 and 12. One or more pumping plates 910can be disposed around the outer perimeter of the workpiece 114 tofacilitate process gas flow.

In embodiments, the apparatus 100 can include a controller 175. Thecontroller 175 controls various components in processing chamber 110 todirect processing of workpiece 114. For example, controller 175 can beused to control heat sources 140. Additionally and/or alternatively,controller 175 can be used to control the door 180. The controller 175can include, for instance, one or more processors and one or more memorydevices. The one or more memory devices can store computer-readableinstructions that when executed by the one or more processors cause theone or more processors to perform operations, such as any of the controloperations described herein.

In certain embodiments, the apparatus 100 is configured to include arotation mechanism capable of rotating the workpiece 114. For instance,during processing of the workpiece 114 (e.g., thermal processing) theworkpiece 114 can be continually rotated such that heat generated by theone or more heat sources 140 can evenly heat the workpiece 114. In someembodiments, rotation of the workpiece 114 forms radial heating zones onthe workpiece 114, which aid in heating the workpiece 114 uniformly andcan provide good temporal control during the heating cycle.

For example, as shown in FIGS. 1-5, the apparatus 100 includes arotation mechanism including a rotation shaft 900. The rotation shaft900 is disposed such that it passes through the dielectric window 108and into the processing chamber 110. The rotation shaft 900 isconfigured to support the workpiece support 112 in the processingchamber 110. For example, the rotation shaft 900 is coupled on one endto the workpiece support 112 and is coupled about the other end to amagnetic actuator 920 capable of rotating the rotation shaft 900 360°.The magnetic actuator 920 can be any device capable of generatingmagnetic forces. For instance, the magnetic actuator 920 can generate amagnetic force field that is capable of influencing the rotation shaft900, such that the rotation shaft 900 can be rotated about its centeraxis.

In certain embodiments, it will be appreciated that a portion of therotation shaft 900 is disposed in the processing chamber 110 whileanother portion of the rotation shaft 900 is disposed outside theprocessing chamber 110 in a manner such that a vacuum pressure can bemaintained in the processing chamber 110. For example, during processingof the workpiece 114 a vacuum pressure may need to be maintained in theprocessing chamber 110. Additionally, the workpiece 114 will need to berotated during processing. Accordingly, the rotation shaft 900 ispositioned through the dielectric window 108 and in the processingchamber 110, such that the rotation shaft 900 can facilitate rotation ofthe workpiece 114 while a vacuum pressure is maintained in theprocessing chamber 110.

In embodiments, the magnetic actuator 920 can include a rotary motionfeedthrough device for coupling rotary motion with the rotation shaftthat includes a dynamic magnetic seal formed of magnets separated bypole rings, which rings can be formed integral with the shaft to form amagnetic system which rotates with the shaft. Suitable examples ofrotary motion feedthrough systems are described in U.S. Pat. No.5,975,536, which is incorporated by reference herein.

Ferrofluid sealed rotary feedthroughs are well known in the art asdevices for transmitting motion through the walls of vacuum chambers. Atypical rotary motion feedthrough device 923 is shown in FIGS. 6 and 7.The rotary motion feedthrough device employs a housing 910, bearings 912and rotation shaft 900, together with a magnet system 916 that isnon-rotatably fixed within the housing 910. The magnet system 916comprises at least one ring magnet 918 and associated magnetic polepiece components 917. Small annular gaps 922 bounded by the outside ofthe shaft and the inside of the pole piece components are filled withferrofluid 924 (a colloidal suspension of ferromagnetic particles in alow vapor pressure fluid), which is held in place by the intensemagnetic field generated by the magnet system 916. The ferrofluidpermits the rotation shaft 900 to turn freely but serves to block theflow of gas axially along the shaft. The particular design shown inFIGS. 5 and 6 uses four ring magnets 918 and five pole rings 917 toproduce eight sealing gaps 922. Other magnetic designs e.g., one ringmagnet with two pole rings are well known.

Sealing is accomplished in two places in rotary feedthroughs. The firstseal is the dynamic seal provided by the ferrofluid between the rotationshaft 900 and pole pieces 917. The second is the static seal provided byO-rings 930 or other materials which seal the spaces between the housingand the outer diameter of the pole piece 917.

The rotation shaft 900 can be formed of ferromagnetic material capableof being influenced by a magnetic force. In embodiments, the rotationshaft 900 can be formed of a ferromagnetic material suitable for use inthe intended process (vacuum) environment in which one end of therotation shaft 900 is exposed to the ambient atmosphere 926, and theopposite end extends through one or more dielectric windows (e.g.,dielectric window 108) into a vacuum environment in the processingchamber 110. For instance, magnetic stainless steels (e.g., 17-4PH) maybe used as a material for the rotation shaft 900 for most applications.Several ferromagnetic stainless steels are well known as suitablematerials for ferrofluid rotary feedthroughs. Any of them may be used inconnection with this disclosure.

In other embodiments, the rotation shaft 900 can be coupled to atranslation device that is capable of moving the rotation shaft 900 andthe workpiece support 112 up and down in a vertical manner. (Not shown).For example, when loading or unloading workpiece 114 from the processingchamber 110, it may be desired to raise the workpiece 114 via theworkpiece support 112 so that removal devices can be used to easilyaccess the workpiece 114 and remove it from the processing chamber 110.Example removal devices may include robotic susceptors. In otherembodiments, the workpiece support 112 may need to be vertically movedin order to provide routine maintenance on the processing chamber 110and elements associated with the processing chamber 110. Suitabletranslations devices that may be coupled to the rotation shaft 900include bellows or other mechanical or electrical devices capable oftranslating the rotation shaft 900 in a vertical motion.

Referring now to FIGS. 8-12, in embodiments, the magnetic actuator 920can include a magnetic levitation device 950 disposed around theworkpiece 114. For example, in certain embodiments, the magneticlevitation device 950 is disposed around the workpiece 114 around theoutside wall of the processing chamber 110. In other embodiments, it iscontemplated that the magnetic levitation device can be disposed in theprocessing chamber 110. Still in other embodiments, certain componentsof the magnetic levitation device 950, for example rotors, can bedisposed inside the processing chamber 110 and other components of themagnetic levitation device 950, such as magnets, can be disposed outsidethe wall of the processing chamber 110. The magnetic levitation device950 is capable of generating a magnetic field for levitating androtating the workpiece 114. The magnetic levitation device 950 ispositioned around the processing chamber 110 and can be secured at afixed location. For example, during processing, the workpiece 114 isplaced on one or more pins 115 atop the workpiece support 112. Themagnetic levitation device 950 is positioned with respect to theworkpiece support 112, such that when the magnetic field is produced bythe magnetic levitation device 950, the workpiece support 112 isrotated, which rotates the workpiece 114. The magnetic levitation device950 can be magnetically coupled to the workpiece support 112. In otherembodiments, it is contemplated that the magnetic levitation device 950is positioned with respect to the workpiece 114, such that when themagnetic field is produced by the magnetic levitation device 950, theworkpiece 114 is lifted from the one or more pins 115 and is rotated bythe magnetic field. As such, in certain embodiments, the magneticlevitation device 950 is configured to move the workpiece 114 in avertical direction. The magnetic levitation device 950 can include thoseavailable from Levitronics, in Zurich, Switzerland.

FIG. 13 illustrates an example post plasma gas injection at a separationgrid according to example embodiments of the disclosure. FIG. 13 will bediscussed with reference to the processing apparatus 100 of FIG. 1 byway of example.

According to example aspects of the present disclosure, the processingapparatus 100 can include one or more gas ports 1000 configured toinject a gas into the neutral species flowing through the separationgrid 200. For instance, a gas port 1000 can be operable to inject a gas(e.g., a cooling gas) between grid plates in a multi-plate separationgrid. In this way, the separation grid can provide post plasma gasinjection into the neutral species. The post plasma gas injection canprovide a number of technical effects and benefits. For example, the gascan be injected to control uniformity characteristics of a process. Forexample, a neutral gas (e.g., inert gas) can be injected to controluniformity, such as uniformity in a radial direction with respect to theworkpiece. Cooling gas can be injected to control the energy of radicalspassing through the separation grid.

The separation grid 200 can be a multi-plate separation grid (e.g., adual-plate grid shown in FIG. 1, a three-plate grid, a four-plate grid,etc.). As shown in FIG. 13, the processing apparatus 100 can include agas port 1000 configured to inject a gas 1002 between grid plate 210 andgrid plate 220, such as in the channel formed between grid plate 210 andgrid plate 220. More particularly, the mixture of ions and neutralspecies generated in the plasma can be exposed to grid plate 210. Thegas port 1000 can inject a gas 1002 or other substance into neutralspecies flowing through the grid plate 210. Neutral species passingthrough grid plate 220 can be exposed to a workpiece. In someembodiments, the gas port 1000 can inject a gas 1002 directly into theprocessing chamber 110 at a location below the separation grid 200 andabove the surface of the workpiece 114.

The gas 1002 or other substance from the gas port 1000 can be at ahigher or lower temperature than the radicals coming from the plasmachamber 120 or can be the same temperature as the radicals from theplasma chamber 120. The gas can be used to adjust or correct uniformity,such as radical uniformity, within the plasma processing apparatus 100,by controlling the energy of the radicals passing through the separationgrid 200. The non-process gas may include a dilution gas, such asnitrogen (N₂) and/or an inert gas, such as helium (He), argon (Ar) orother inert gas. In some embodiments, the gas 1002 can be an inert gas,such as helium, nitrogen, and/or argon.

In embodiments, the processing apparatus can have a dual configurationas shown in FIGS. 14-15. For example, the processing apparatus 1200includes plasma chambers 120 a,120 b and processing chambers 110 a,110b. In embodiments, the processing chambers 110 a,110 b can be divided bya wall 1202. In other embodiments, however, it is contemplated that theprocessing chamber 110 includes an undivided processing chamber. Asshown, a workpiece supports 112 a,112 b are disposed in the processingchambers 110 a,110 b for supporting workpieces 114 a,114 b. One or moreheat sources 140 a,140 b are disposed on an opposite side of theprocessing chambers 110 a,110 b from the plasma chambers 120 a,120 b.One or more separation grids 200 a,200 b separate the processingchambers 110 a,110 b from the plasma chambers 120 a,120 b. One or moredielectric windows 108 a,108 b are disposed between the heat sources 140a,140 b and the workpiece supports 112 a,112 b.

The apparatus 1200 can include gas delivery systems 155 a,155 bconfigured to deliver process gas to the processing chambers 110 a,110b, for instance, via gas distribution channels 151 a,151 b or otherdistribution system (e.g., showerhead). The gas delivery systems 155a,155 b can include a plurality of feed gas lines 159 a,159 b. The feedgas lines 159 a,159 b can be controlled using valves 158 a,158 b and/orgas flow controllers 185 a,185 b to deliver a desired amount of gasesinto the plasma chamber as process gas. The gas delivery systems 155a,155 b can be used for the delivery of any suitable process gas.Control valves 158 a,158 b can be used to control a flow rate of eachfeed gas line to flow a process gas into the processing chambers 110a,110 b. In embodiments, the gas delivery systems 155 a,155 b can becontrolled with gas flow controllers 185 a,185 b. In embodiments, thegas distribution system 155 can be a unitary system including feed gaslines 159 coupled to a single gas distribution line capable ofdelivering process gas into plasma chambers 110 a,110 b via gasdistribution channels 151 (not shown in the figures).

As shown in FIG. 15, rotation shafts 900 a,900 b are coupled to theworkpiece supports 112 a,112 b for rotating the workpiece supports 112a,112 b in the processing chamber 110 a,110 b. The rotation shafts 900a,900 b are coupled to magnetic actuators 920 a,920 b. Portions of therotation shafts 900 a,900 b may be disposed in the processing chambers110 a,110 b, while other portions of the rotations shafts 900 a,900 bare disposed outside of the processing chambers 110 a,110 b, such that avacuum pressure can be maintained in the processing chambers 110 a,110 bwhile the rotation shafts 900 a,900 b facilitate rotation of workpieces114 a,114 b. In other embodiments, as shown in FIG. 16, the rotationsystem includes magnetic actuators comprising magnetic levitationdevices 950 a,950 b disposed in the processing chambers 110 a,110 b. Forexample, the magnetic levitation devices can be securely fixed aroundthe workpiece supports 112 a,112 b and/or the workpieces 114 a,114 b.The magnetic levitation devices 950 a,950 b are secured at fixedlocations in the interior of the processing chambers 110 a,110 b.

Such dual configurations allow for the processing of multipleworkpieces. For example, a workpiece can be transferred and processed inprocessing chamber 110 a while another workpiece is simultaneouslyprocessed in processing chamber 110 b. For example, the workpiece in thefirst processing chamber 110 a can be processed via a suitable plasmaand/or thermal treatment while another workpiece in the secondprocessing chamber 110 b can be processed via a suitable plasma and/orthermal treatment.

Referring now to FIG. 16, illustrated is an example pumping plate 910that can be used in embodiments provided. The pumping plate 910 includesone or more pumping channels 912, 913 for the flow of gas through theprocessing chamber 110. For example, the pumping the pumping plate 910can include a continuous pumping channel 912 configured around theworkpiece 114. The continuous pumping channel 912 can include an annularopening configured to allow gas to pass from a first side, such as a topside, of the workpiece 114 to a second side, such at the bottom side, ofthe workpiece. The continuous pumping channel 912 can be disposedconcentrically around the guard ring 109. Additional pumping channels913 can be disposed in the pumping plate 910 to facilitate gas movementwithin the processing chamber 110. A guard ring 109 can be used tolessen edge effects of radiation from one or more edges of the workpiece114. The guard ring 109 can be position around the perimeter of theworkpiece 114.

The pumping plate 910 can be or include a quartz material. Furthermore,in some embodiments, pumping plate 910 can be or include hydroxyl dopedquartz. Hydroxyl doped quartz can exhibit desirable wavelength blockingproperties in accordance with the present disclosure.

FIG. 17 depicts a flow diagram of one example method (700) according toexample aspects of the present disclosure. The method (700) will bediscussed with reference to the processing apparatus 100 of FIG. 1 byway of example. The method (700) can be implemented in any suitableplasma processing apparatus. FIG. 17 depicts steps performed in aparticular order for purposes of illustration and discussion. Those ofordinary skill in the art, using the disclosures provided herein, willunderstand that various steps of any of the methods described herein canbe omitted, expanded, performed simultaneously, rearranged, and/ormodified in various ways without deviating from the scope of the presentdisclosure. In addition, various steps (not illustrated) can beperformed without deviating from the scope of the present disclosure.

At (702), the method can include placing a workpiece 114 in a processingchamber 110 of a plasma processing apparatus 100. The processing chamber110 can be separated from a plasma chamber 120 (e.g., separated by aseparation grid assembly). For instance, the method can include placinga workpiece 114 onto workpiece support 112 in the processing chamber 110of FIG. 1. The workpiece 114 can include one or more layers comprisingsilicon, silicon dioxide, silicon carbide, one or more metals, one ormore dielectric materials, or combinations thereof.

At (704) the method includes admitting a process gas to the plasmachamber. For example, a process gas can be admitted to the plasmachamber 120 via the gas delivery system 155 including a gas distributionchannel 151. The gas delivery system 155 can be used to deliver aprocess gas capable of etching at least one material layer from theworkpiece 114. For example, the process gas can includeoxygen-containing gases (e.g. O₂, O₃, N₂O), hydrogen-containing gases(e.g., H₂, D₂), nitrogen-containing gases (e.g. N₂, NH₃, N₂O),fluorine-containing gases (e.g. CF₄, C₂F₄, CHF₃, CH₂F₂, CH₃F, SF₆, NF₃),hydrocarbon-containing gases (e.g. CH₄), or combinations thereof. Insome embodiments, the process gas can be mixed with an inert gas thatcan be called a “carrier” gas, such as He, Ar, Ne, Xe, or N₂. A controlvalve 158 can be used to control a flow rate of each feed gas line toflow a process gas into the plasma chamber 120. A gas flow controller185 can be used to control the flow of process gas.

At (706) the method includes generating one or more species from theprocess gas using a plasma induced in the plasma chamber 120. Forexample, to generate one or more species or radicals, the induction coil130 can be energized with RF power from the RF power generator 134, togenerate a plasma from the process gas in the plasma chamber 120. Theplasma generated can include one or more species including radicals.Suitable radicals can include etchant radicals capable of removingportions of material or material layer from a workpiece. Other radicalscan be generated that can modify surface properties of the workpiece114. For example, radicals can be generated that can selectively depositmaterial layers on portions of the workpiece. Radicals can be generatedthat are capable of modifying the chemical or material composition ofmaterial layers on the workpiece, including but not limited to surfacecleaning, surface smoothing, materials oxidation, materials nitridation,materials doping, etc. Examples of suitable radicals include, hydrogenradicals, oxygen radicals, fluorine radicals, and combinations thereof.In some embodiments, the plasma generated in the plasma chamber is aremote plasma containing one or more radicals, such as hydrogenradicals, fluorine radicals, oxygen radicals, and combinations thereof.

At (708) the method includes filtering the one or more species togenerate a filtered mixture. To create a filtered mixture the one ormore species can be filtered via a separation grid 200 that separatesthe plasma chamber 120 from the processing chamber 110 to generate thedesired radicals. The separation grid 200 can be used to perform ionfiltering from a mixture generated by plasma in the plasma chamber 120to generate a filtered mixture. The filtered mixture may contain one ormore radicals.

In some embodiments, the separation grid 200 can be configured to filterions with an efficiency greater than or equal to about 90%, such asgreater than or equal to about 95%. A percentage efficiency for ionfiltering refers to the amount of ions removed from the mixture relativeto the total number of ions in the mixture. For instance, an efficiencyof about 90% indicates that about 90% of the ions are removed duringfiltering. An efficiency of about 95% indicates that about 95% of theions are removed during filtering.

In some embodiments, the separation grid can be a multi-plate separationgrid. The multi-plate separation grid can have multiple separation gridplates in parallel. The arrangement and alignment of holes in the gridplate can be selected to provide a desired efficiency for ion filtering,such as greater than or equal to about 95%.

In some embodiments, one or more separation grid plates can include oneor more cooling channels disposed therein. The method can includecooling the one or more separation grids by pumping fluid through one ormore cooling channels.

Further, in some embodiments the method includes admitting a non-processgas through one or more gas injection ports at or below the separationgrid to adjust energy of radicals passing through the separation grid.

At (710) the method includes exposing the workpiece to the filteredmixture. The filtered mixture can include one or more radicals capableof modifying a surface of the workpiece 114. For example, the filteredmixture can include one or more radicals capable of stripping materialfrom the workpiece 114. In other embodiments, the filtered mixture caninclude one or more radicals capable of depositing material layers onthe workpiece. In other embodiments, the filtered mixture can includeone or more radicals capable of modifying the chemical composition orchemical or mechanical properties of one or more material layers on thesurface of the workpiece.

At (712) the method includes rotating the workpiece 114 in theprocessing chamber 110. For example, the workpiece 114 can be rotated inthe processing chamber while radiation is emitted from heat source 140.As shown in FIG. 1, the rotation shaft 900 is coupled to the workpiecesupport 112 and is also coupled to a magnetic actuator 920. The magneticactuator 920 can be used to rotate the rotation shaft 900 therebyrotating the workpiece support 112, and the workpiece 114 thereon. Inother embodiments, the workpiece 114 can be rotated by a magneticlevitation device 950. For example, as shown in FIG. 8, the magneticlevitation device 950 can be magnetically coupled to the workpiecesupport 112, such that magnetic forces created by the magneticlevitation device 950 can rotate the workpiece support 112 and theworkpiece 114 thereon in the processing chamber 110. In otherembodiments, the magnetic levitation device 950 can be magneticallycoupled to the workpiece 114, such that magnetic forces created by themagnetic levitation device 950 can lift the workpiece 114 from theworkpiece support 112 and rotate the workpiece 114.

At (714) the method includes emitting radiation directed at one or moresurfaces of the workpiece to heat the workpiece. For example, one ormore heat sources 140 can include one or more heating lamps 141. Forexample, heat sources 140 including one or more heating lamps can emitelectromagnetic radiation to heat workpiece 114. Example heat sources140 as described herein can be used. In certain embodiments, directiveelements, such as for example, reflectors (e.g., mirrors) can beconfigured to direct electromagnetic radiation from one or more heatinglamps 141 towards a workpiece 114 and/or workpiece support 112.

Exposing the workpiece 114 to the filtered mixture, rotating theworkpiece, and emitting radiation at the workpiece can be alternateduntil desired processing of the workpiece is achieved. In otherembodiments, it may be desired to expose the workpiece 114 to thefiltered mixture while simultaneously emitting radiation at theworkpiece to heat the workpiece. Depending on process parameters,process gas can be removed from the processing chamber 110 via one ormore gas exhaust ports 921.

In some embodiments, as indicated by the various arrows in FIG. 10 themethod can include the listed steps in a variety of orders orcombinations. For example, in certain embodiments, the workpiece 114 maybe placed in the processing chamber 110 and exposed to radiation beforeplasma treatment of the workpiece 114. Exposing the workpiece 114 to thefiltered mixture, emitting radiation at the workpiece 114, and rotatingthe workpiece 114 can be alternated until desired processing of theworkpiece 114 is achieved. In other embodiments, it may be desired toexpose the workpiece 114 to the filtered mixture while simultaneouslyemitting radiation at the workpiece 114 to heat the workpiece. Indeed,for uniform workpiece 114 heating, the workpiece 114 can be rotatedwhile being exposed to radiation. The steps provided herein can bealternated or repeated in any manner depending on the desired processingparameters.

In other embodiments, it is contemplated that the workpiece 114 can beplaced in the processing chamber 110 and then the workpiece 114 can beexposed to radiation, for example to heat the workpiece 114 to a certainprocessing or pre-processing temperature. After the workpiece 114achieves the pre-processing temperature the workpiece 114 can be exposedto the desired thermal treatment and/or plasma treatment.

At (716) plasma generation is stopped, gas flow into either the plasmachamber and/or the processing chamber is stopped, and radiationemittance is stopped, thus ending workpiece processing.

At (718) the method includes removing the workpiece from the processingchamber 110. For instance, the workpiece 114 can be removed fromworkpiece support 112 in the processing chamber 110. The plasmaprocessing apparatus can then be conditioned for future processing ofadditional workpieces.

Further aspects of the invention are provided by the subject matter ofthe following clauses:

A method for processing a workpiece in a processing apparatus, themethod comprising: placing the workpiece on a workpiece support disposedin a processing chamber; admitting one or more process gases to a plasmachamber; generating one or more species from the one or more processgases in a plasma using an inductively coupled plasma source in theplasma chamber; filtering the one or more species with one or moreseparation grids to create a filtered mixture containing one or moreradicals; exposing the workpiece to the filtered mixture containing oneor more radicals; emitting, by one or more radiative heat sources,radiation directed at one or more surfaces of a workpiece to heat atleast a portion of a surface of the workpiece; and rotating theworkpiece in the processing chamber via a rotation system including amagnetic actuator.

The method of any preceding clause, wherein the rotation system includesa rotation shaft coupled to the magnetic actuator, the rotation shaft atleast partially disposed in the processing chamber.

The method of any preceding clause, wherein a first portion of therotation shaft is disposed in the processing chamber and a secondportion of the rotation shaft is disposed outside the processing chambersuch that a vacuum pressure can be maintained in the processing chamber.

The method of any preceding clause, wherein the magnetic actuator isdisposed at a fixed location in the processing chamber.

The method of any preceding clause, wherein the magnetic actuatorcomprises a magnetic levitation system capable of producing a magneticfield to rotate the workpiece.

The method of any preceding clause, further comprising maintaining avacuum pressure in the processing chamber.

The method of any preceding clause, further comprising removing gas fromthe processing chamber using one or more exhaust ports.

The method of any preceding clause, further comprising disposing apumping plate around the workpiece, the pumping plate providing one ormore channels for the directing a flow of process gas through theprocessing chamber.

The method of any preceding clause, wherein the process gas comprise anoxygen-containing gas, a hydrogen-containing gas, a nitrogen-containinggas, a hydrocarbon-containing gas, a fluorine-containing gas, orcombinations thereof.

The method of any preceding clause, comprising alternating exposing theworkpiece to the filtered mixture containing one or more radicals andemitting, by one or heat sources, radiation directed at one or moresurfaces of a workpiece to heat at least a portion of a surface of theworkpiece.

The method of any preceding clause, comprising removing process gas fromthe processing chamber using one or more exhaust ports.

The method of any preceding clause, comprising cooling the one or moreseparation grids by pumping fluid through one or more cooling channelsdisposed in the one or more separation grids.

The method of any preceding clause, further comprising stopping plasmageneration, the flow of process gas, or emitting radiation.

The method of any preceding clause, further comprising removing theworkpiece from the processing chamber.

The method of any preceding clause, further comprising admitting anon-process gas through one or more gas injection ports at or below theseparation grid to adjust energy of radicals passing through theseparation grid.

While the present subject matter has been described in detail withrespect to specific example embodiments thereof, it will be appreciatedthat those skilled in the art, upon attaining an understanding of theforegoing may readily produce alterations to, variations of, andequivalents to such embodiments. Accordingly, the scope of the presentdisclosure is by way of example rather than by way of limitation, andthe subject disclosure does not preclude inclusion of suchmodifications, variations and/or additions to the present subject matteras would be readily apparent to one of ordinary skill in the art.

What is claimed is:
 1. A processing apparatus for processing aworkpiece, the processing apparatus comprising: a processing chamber; aplasma chamber separated from the processing chamber, the plasma chamberdisposed on a first side of the processing chamber; a gas supply systemconfigured to deliver one or more process gases to the plasma chamber; aplasma source configured to generate a plasma from the one or moreprocess gases in the plasma chamber; a workpiece support disposed withinthe processing chamber, the workpiece support configured to support aworkpiece, wherein a back side of the workpiece faces the workpiecesupport; one or more radiative heat sources configured on a second andopposite side of the first side of the processing chamber, the radiativeheating sources configured to heat the workpiece from the back side ofthe workpiece; a dielectric window disposed between the workpiecesupport and the one or more radiative heat sources; and a rotationsystem configured to rotate the workpiece, the rotation systemcomprising a magnetic actuator.
 2. The processing apparatus of claim 1,wherein the rotation system comprises a rotation shaft passing throughthe dielectric window, the rotation shaft configured to rotate theworkpiece support in the processing chamber, wherein the rotation shaftis coupled to the magnetic actuator.
 3. The processing apparatus ofclaim 2, wherein a first portion of the rotation shaft is disposed inthe processing chamber and a second portion of the rotation shaft isdisposed outside the processing chamber such that a vacuum pressure canbe maintained in the processing chamber.
 4. The processing apparatus ofclaim 3, wherein the second portion of the rotation shaft is coupled tothe magnetic actuator.
 5. The processing apparatus of claim 1, whereinthe magnetic actuator is disposed around the workpiece.
 6. Theprocessing apparatus of claim 5, wherein the magnetic actuator comprisesa magnetic levitation system.
 7. The processing apparatus of claim 6,wherein the magnetic levitation system can move the workpiece in avertical direction.
 8. The processing apparatus of claim 1, wherein theplasma source is an inductively-coupled plasma source.
 9. The processingapparatus of claim 8, wherein a grounded Faraday shield is disposedbetween the inductively-coupled plasma source and the plasma chamber.10. The processing apparatus of claim 1, wherein the plasma chamber andprocessing chamber are separated via one or more separation grids. 11.The processing apparatus of claim 10, wherein the one or more separationgrids comprise one or more cooling channels disposed therein.
 12. Theprocessing apparatus of claim 11, wherein a fluid is pumped through theone or more cooling channels to cool the one or more separation grids.13. The processing apparatus of claim 12, wherein the fluid compriseswater.
 14. The processing apparatus of claim 10, further comprising oneor more gas injection ports configured to inject gas between one or moreseparation grids.
 15. The processing apparatus of claim 10, wherein theone or more separation grids are disposed such that one or more processgases can pass through the one or more separation grids into theprocessing chamber and expose a topside of the workpiece to the one ormore process gases.
 16. The processing apparatus of claim 10, whereinthe one or more separation grids are disposed such that the plasma canbe filtered forming a filtered mixture in the processing chamberexposing a topside of the workpiece to the filtered mixture.
 17. Theprocessing apparatus of claim 1, wherein the dielectric window comprisesquartz.
 18. The processing apparatus of claim 1, further comprising apumping plate disposed around the workpiece, the pumping platecomprising one or more channels for directing a flow of gas through theprocessing chamber.
 19. The processing apparatus of claim 1, wherein theone or more radiative heating sources are configured to emit broadbandradiation to heat the workpiece.
 20. The processing apparatus of claim1, wherein the processing chamber is configured to maintain a vacuumpressure.